1. Field of the Invention
The present invention relates to the structure of a switch operating rubber member for pressing a switch section composed of an electrically conductive section and a pattern on a substrate.
2. Description of the Related Art
FIGS. 9, 10A and 10B show cross-sectional views of the structure of a push type switch as an example of conventional push type switches. The push type switch mainly comprises main bodies 51 and 61, operation buttons 52 and 62 which are movable in an up and down direction, diaphragm 53 and 63, and printed circuit boards 55 and 65 having electrical contacts 55a and 65a. In this push switch, when the operation buttons 52 and 62 are pressed, the electrically conductive rubbers 54 and 64 come into contact with the electrical contacts 55a and 65a, whereby an ON signal is output.
However, in the push type switch shown in FIG. 9, the stroke of the operation button 52 is determined by the contact pattern disposed below it such that the switch cannot be operated by pressing the button through a stroke having a length other than a predetermined amount. Further, it is difficult to dispose the switch in a thin space because the diaphragm 53, the electrically conductive rubber 54 and the printed circuit board 55 are disposed below the operation button in an overlapped state.
Further, in the push type switch shown in FIGS. 10A and 10B, when the operation button 62 is pressed as shown in FIG. 10B, which shows the turned-ON state of the switch, there is a possibility that the diaphragm 63 is unevenly flexed and the operation button 62 is inclined. When the operation button 62 is inclined, there is a possibility for the occurrence of a disadvantage in which the operation button 62 is caught by the inner wall of the main body 61 so that the operation button 62 cannot be returned to its original position even if the pressing force is released therefrom. Conventionally, it is an ordinary practice to make the operation button guide section of the main body 61 thicker toward the outside as well as to increase the length of the operation button 62 to prevent the operation button 62 from becoming caught under the main body, which makes the miniaturization of such equipment difficult.